Evaluation of hearing results in otosclerotic patients after stapedectomy.

INTRODUCTION
Otosclerosis one of the most common causes of conductive hearing loss is more common in females and in their middle ages. It is usually a bilateral and progressive disease. Surgical operation is suggested as the exclusive management of otosclerosis. This study aims to evaluate the hearing results after stapedectomy in otosclerotic patients in Ahwaz.


MATERIALS AND METHODS
In this case series study, the records of otosclerotic patients who had undergone stapedectomy or stapedotomy in Imam Khomeini and Apadana Hospitals of Ahwaz, Iran during 1997-2007 were evaluated. All the operations were performed by a single surgeon (first author). Data were analyzed using SPSS and descriptive statistical tests.


RESULTS
One hundred ninety seven patients were included in this study. 66.8% were female and the age range was 20-40 years. The affected ears were reported as follows: right ear (65%), left ear (35%) and bilateral (18%). ABG was reported as less than 10db in 63.9% of patients; between 10 to 20db in 29.99% and more than 20db in 5%. Surgical complications were observed in 4.5% of patients (1.5% intraoperatively and 3% postoperatively).


DISCUSSION
Saccular dysfunction seems to be an important finding in SSNHL. Although it is more prevalent in the patients with vertigo, it can be found in the non-dizzy cases. VEMP disturbance in SSNHL shows more extensive pathological involvement.


CONCLUSION
Just like previously conducted studies, satisfactory surgical outcomes with rare complications were observed in the appropriate population under study.


Introduction
Otosclerosis is one of the most common causes of conductive hearing loss in people with 15-50 years of age. Otosclerosis has been derived from a Greek word meaning ear hardening.
The disease now refers to the bony ear capsule and may result in progressive and conductive hearing loss, mixed hearing loss and also absolute sensorineural hearing loss in some rare cases (1).
Otosclerosis is an hereditary disease which is transmitted in an autosomal dominant form with incomplete penetrance (1).
Bilateral otosclerosis has been observed in 60% of patients (2). Otosclerosis occurs most commonly among Caucasions with an incidence of 1% followed by Asians at 0.5%, African-American men at 7.3% and African-American women at 10.3% (1).
Progressive and conductive hearing loss particularly in low frequencies  Hz) which may sometimes occur with sensorineural hearing loss has been identified as the main clinical finding of otosclerosis (1). Tinnitus has been reported as the other common symptom of this disease (2). There is not any definitive medical treatment for the disease; however, some surgical methods such as stapedectomy or stapedotomy may be effective in the treatment of hearing loss.
Stapedectomy includes removal of the stirrup, creating a small bone in the Foot plate and inserting prosthesis in between the incus and the oval window (3). The related complications of stapedectomy include: sensorineural hearing loss, dizziness, facial nerve paralysis, tinnitus, degradation of taste, eardrum perforation, perilymph otorrhea and perilymph fistula. Delayed treatment may lead to otosclerosis progression and permanent deafness; so the disease should be diagnosed in early stages and stapedectomy has to be performed as the treatment of choice for improvement of this disease (2).
In order to specify whether the optimal surgical outcome has been obtained and whether it has had any significant effect on  Deafness occurred in 2 patients (1%) after the surgery ( Table 2). The mean AC of the studied cases' was reported as 55.5 db preoperatively which reached to 27.5 db after the operation. Also the patients showed a mean ABG of about 33.6db preoperatively and 11.9 db postoperatively.

Discussion
Otosclerosis is one of the most common diseases involving the ear capsule. This disease occurs only in humans and is more common in middle aged women. Otosclerosis has been diagnosed as the most common cause of conductive hearing loss. It may even progress in to permanent deafness.
Histopathologically, the otosclerosis process is divided in to two phases including the early phase and the late phase. Increased vascularity, hyperemia and bone resorption characterize the early phase. In the late phase, the reabsorbed bone is replaced with dense selerotic bone. Other studies revealed the same results relatively (4,(9)(10)(11)(12)(13)(14)(15)(16). In a study on 34 Malaysian patients during 1996-2002, postoperative complications were observed in 2 cases (5.9%) which shows a similarity between their reported results and ours (14). According to the study conducted by Dr.
Karimi and his colleagues in Tehran University in 2005, Stapedectomy was introduced as a more desired method in comparison to Stapedotomy in improving ABG incision (17).

Conclusion
Regarding the obtained results, the frequency of otosclerosis in Iran is as high as other countries worldwide. Women are affected more than men and just like other similar studies, the most common involved age was 20-40 years. Most cases were affected with unilateral otosclerosis which is in contrast to other studies. More accurate investigations on a larger group of patients with different ethnicities are required in this regard. The number of studied parameters should also be increased. More extensive and accurate patients' data collection is also highly recommendable. Moreover, it should be kept in mind that the noticeable improvement in a patient's hearing is the direct result of a successful surgical operation.